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How long will a boy willing near the win...

How long will a boy willing near the window of a train travelling at `36kmh^(-1)` sec a train passing by in the opposite direction with a speed of `18kmh^(-1)`. The length of slow-moving train is 90m.

Text Solution

Verified by Experts

The relative velocity of the slow-moving train with respect
to the boy is `=(36+18)kmh^(-1)=54xx(5)/(18)ms^(-1)=15ms^(-1)`.
Since the boy will watch the full length of the other train, to find the time taken to watch full train:
We have,
`15=(90)/(t)ort=(90)/(15)=6s`
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